Electric pulse generating systems



May l, 1952 J. A. T. FRENCH 3,032,747

ELECTRIC PULSE GENERATING SYSTEMS Filed Dec. 27, 1956 4 Sheets-Sheet 1sPl PIL sPz sPs SL SP5 g SP7 sPlo luNn LPA Pw R5 RI R2 2 5@ 5@ 1f MRIDI' f LPD \\F/G.2. @um @me @Rw @no frounns [ig:A i I .i

srz sPs SP1 sPlo nel@ L BY mar ffy/3%- ATTORNEY May l, 1962 J, A. T.FRENCH NERATING SYSTEMS ELECTRIC PULSE GE 4 Sheets-Sheet 3 Filed DSC.27, 1956 ORS PULSE NERAT i 2 ECP E, P-PULSES gri- TRANSLATION PULSES INIDO-PULSE CYCLE IRS TRIGGER R S' TRANSLATION STORAGE G ES lNvEN'rbR mesf4.7.--7elk/I, BY 7Mr/'7mA-f1-:QQNBY A Cfg I I E PULSE RESHAP May 1,1962 J. A. T. FRENCH 3,032,747

ELECTRIC PULSE GENERATING SYSTEMS Fild Dec. 27, 1956 4 Sheets-Sheet 4 4P200 l l cOOe TRANSLATION PzoI P400 cPz OOO: TRANSLATION P(2oo n -T+I)t200m cPz COOL ANO TRANSLATION IPULSES IOOI IOO IOOl Ioo I loo' IOOAtllllllllllllllllllllllllllllllll||l||||||IIIIIHIIIHIIIIIIIIIHIIHIIl|ll|||||llllllllllllllllIIHIIHIIIIIIIIH-IH PI-IOO zoo I IoO I IOo j lO- PULSE|IOI-zoo -200 IOI zoo IoI' zoo IOI 20o TRANSLATION GATINO PULSE FIG. 8

lNveN-ron BY f4# 47% A-rToIzNeY United States Patent C) M 3,032,747ELECTRIC PULSE GENERATING SYSTEMS James Alfred Thomas French, Kenton,England, assignor to Her Maiestys Postmaster General, London, EnglandFiled Dec. 27, 1956, Ser. No. 630,995 Claims priority,`application GreatBritain Dec. 29, 1955 2 Claims. (Cl. S40-172.5)

This invention relates to register-translators.

According to the present invention a register translator comprises aplurality of transformer cores, an input winding for each core, aplurality of pulse train generators, connections from said generators tosaid input windings, a number of code wires each inductively coupled bysaid cores to a selection of said input windings, and, a number oftranslation wires each inductively coupled by said cores to anotherselection of said input windings, each translation wire correspondingwith one of said code wires, rectiers series connected with said codewires and said translation wires, biassing means for rendering saidrectiiiers normally non-conductive, pulsing means connected to both saidcode wires and said translation wires, coincidence detection means,means-code output equipment-for cyclically presenting coded pulses tosaid detection means, means Lfor connecting said code wires to saiddetection means, translation storage apparatustranslation storage-gatingmeans connected between said translation wires and said translationstorage apparatus for gating into said storage apparatus the output of atranslation Wire upon coincidence being detected by said coincidencedetecting means.

Examples of the invention will now be described in greater detail withreference to the accompanying drawings of which:

FIG. l illustrates the basic principle of the invention,

FIGS. 2 and 3 illustrate `alternative methods of combining pulses bymeans of coupling circuits,

FIG. 4 shows a hysteresis curve,

FIG. 5 shows the waveforms of pulses used in FIGS. 2 and 3.

FIG. 6 is Aan explanatory block schematic diagram of a form ofregister-translator to which the invention may be applied,

FIG. 7 shows in more detail the register-translator of FIG. 6, and

FIG. 8 shows the waveforms of pulse trains used in FIG. 7.

FIG. l shows a number of transformers having toroidal cores or rings R.Each core has an input primary winding PW connected to a pulse source(not shown) whilst an output or secondary winding of the core compriseslead PR1, PR2 It will be seen that the leads are merely threaded througha selection of the cores R, the selection depending upon the particularcombination of pulses which it is desired to produce on the lead. Theleads PR1, PR2 are shown in FIG. l as being inductively coupled by meansof the toroidal transformers but it will be understood that other formsof inductive couplings may be used and suitable forms of coupling 4areshown in the specification of co-pending patent application No. 603,650.

It is not necessary to provide individual pulse sources for eachtransformer as the `latter can =be used to com- Patented May 1, 1962 ICCbine pulses from several sources. By using combinations of pulses fromseveral sources the number of actual sources required is reduced. Thismethod also considerably reduces the total power requirements as poweris only taken from the pulse sources when the pulses are actually usedand the sources are able to operate more efficiently.

FIG. 2 shows one method of using the toroidal core transformers Rit-R20to combine pulses. Only some of the transformer cores `are shown andeach has a primary winding PW in series with a rectifier MR1. Theseries-connected primary winding and rectifier are connected between twopulse wires each taken from la set 'of pulse wires. One set of pulsewires is drawn vertically in FIG. 2 and consists of ten wires, of whichwires SP1, SP2, SP5, SP6, SP7 and SP10 are shown, While the other set isdrawn horizontally, .and comprises four wires LPA, LPB, LPC and LPD.Only one output or code lead PL is shown in dotted lines in FIG. 2 forthe sake of clarity rand is threaded through cores R1, R7, R12 and R20.

FIG. 5 shows the waveforms and relative durations of the various pulsetrains used in the circuit of FIG. 2. The short pulse trains P1-10 areapplied to Wires SP1-10 respectively, and to ,the leads LPA, LPD isapplied long pulse train LP1 10, whilst long pulse train LP11 20 isapplied to leads LPC, LP-D. It will be observed that if the pulses ofthe trains P1 P10 -are of one unit duration then the pulses of thetrains LPM() and LP11 20 are of 10-unit duration. The horizontal set ofwires is biased to a potential -l-V as shown and the pulses of the pulsetrains LPMO, LP11 20 are connected negative-going and limited at earthpotential. The pulses of the pulse trains P1 to P10 are positive-goingand do not exceed |V in amplitude. Thus, the rectifier MR1 in serieswith the prim-ary winding PW only conducts when a pulse on the verticalwire coincides with the pulse on .the horizontal wire and when thisoccurs the pulse on the vertical wire isy applied to the secondarywinding of the transformer which is the pulse lead PL shown dotted inFIG. 2.

Thus it can be seen from FIG. 2 that each of the vertical wires SP1-10is common to two of the horizontal wires LPA; LPB; LPC; LPD and that thecycle of pulses on wires SP1-10 combined cyclically with the pulses onwires LPA, LPB and LPC, LPD will produce 20 output pulses. That is 20output pulses for 12 input sources.

During a pulse of long pulse train LPMO, coincidence occurs in ringsRl-RS between the pulse and a pulse of each of the pulse trains Pl-PSand then in rings R6-R10 between the pulse and a pulse of each of thepulse trains P6-P10. During a pulse of long pulse train LP11 20,coincidence occurs in rings R11- R15 between the pulse and a pulse ofeach of the pulse trains Pl-PS and then in rings R16-R20 between thepulse and a pulse of each of the pulse trains P6-P10. Since the pulse ofLPM@ immediately succeeds la pulse of LPLM, the pulses P1--10 coincidentwith `a pulse of LP11 20 `are displaced sin time -and therefore pulsesappear successively in rings For each extra pair of horizontal Wiresincluded in the cycle, an extra l0 output pulses is produced i.e. 30output pulses for 13 sources. Thus, the 'addition of two furtherhorizontal wires each carrying pulse train LP21 ,0 as shown in FIG. 5produces 30 output pulses.

connected to a lowV impedance source of pulses.

IP2 and so on.

Each toroidal core transformer thus constitutes a pulse source and itsimpedance when no pulse is being .produced, can be lowered by shuntingthe primary winding of the transformer with a rectifier MRS whichconducts only if a pulse of a. reverse polarity tends to be produced'across the primary winding. This may occur when a large number of pulseleads are threaded through the ring.

Rectiers, especially of the germanium junction type, employed as therectifiers MRI may take an appreciable time in which to restore from theconducting to the nonconducting state and this effect may haveundesirable consequences especially when the duration of the pulsesconnected to wires vSP1-10 are very short, say in the region of lmicrosec. or less. The worst effect will be encountered at the end ofalong pulse on wires LPA LPD.

For instance when a long pulse say LPI- has just gated the tenth pulseP10, the P10 pulse returns to earth while at the same moment the longpulse LPI-10 returns to -l-V. Thus during the time the rectiier takes toreturn to its non-conducting state, a current will flow in V`the windinggiving rise'to a false pulse in the wire PL threading the core. This canbe overcome by using additionallong pulse trains, shown as LP16 25 andLP26 35 in FIG. y5 connected in FIG. 2 so that long pulse trains LPMO isconnected to wire LPA and long pulse train LP11 20 to wire LPC asbefore, vbut withlong pulse trains 1216-25 and LP29 35 vconnected towires LPB and LPD respectively.

With this arrangement LPMO gates the iirst tive pulses P1-5 in positions1-5, while LP11 .20 gates the second ve pulses P6-10 in positions 11-15.This leaves positions `6-1() in LPM() and positions 16-20 in LP11 20 forthe rectillier to return to its non-conducting state before the long:pulses LPM() and 11-20 respectively return to the +V condition.

FIG. 3 shows an alternative method of combining vpulses which arecarried by the same arrangement of Lpulse wires as in FIG. 2. Each ringR1-R20 in FIG. 3 hastwo windings'PWl, PWZ, and is constructed of arectangular hysteresis loop type of magnetic material, such a loop beingshown in FIG. `4. FIG. 4 will be recognised as illustrating the wellvknown hysteresis curve vfora magnetic material showing applied fieldalong the horizontal axis H and magnetic induction along the ver- -ticalaxis B. The windings PW2 on each ring in the horizontal row of rings areconnected in series and a current I passes through them by connectingthem, for example, in the anode circuit of valves such as valve VAwhichis normally conducting and is yfed from a positive supply E. ThewindingsV PWl on the rings in the vertical lrows of rings are connectedin series in two groups using valternate lrings as shown, each group ofwindings being Thus, lead SP1 connected to the PW1 windings of R1 andR11 isfsupplied with-pulse train P1, lead SP2 joined to the -PWllwindings of R2, R12 is supplied with pulse train Negative-going longpulses from `pulse sources LPMO, LP11 20 are applied to the grids of thevvalves VA, VB of'suiicient amplitude to cut off the anode currents andin order toproduce the required ,pulses LPM() is applied to valves VAand VB and LPILZO to valves VC and VD. Only one output or code lead '-PLis shown in dotted lines inFIG. 3 for the sake of fclarity and isthreaded through cores R1, R7, R12 and applied to the same ring causes apulse voltage to appear across Winding PW1 and the operating point onthe on the hysteresis loop. A coincidence between pulses maximum valueof the current I.

Tn of common point CPn.

hysteresis loop to move during the pulse from B to another point, say C.The operating point moves back to A when `a current I is re-applied atthe end of the pulse on the horizontal wire and the leads threadedthrough the rings for a pulse of reverse polarity induced in them.

The current taken from the low impedance sources of the pulses P1, P2.by windings PW1 also passes through the windings of the other ringsconnected in series but must produce no appreciable voltage drop acrossthose windings. The magnetic eltect of current I in windings PW2. must,therefore, always be greater and the efect of the current which iiows inwindings PW1 should ensure that those cores which are saturated by acurrent I remain saturated. This requirement determines the The pulsesources for-med by the rings always have a very low impedance because inany group of rings having windings connected in series to -a source ofpulses P1, P2 Iall the rings except one are saturated Ymagnetically andthatone is effectively connected across the low impedance pulse source.

FIG. 6 shows in block schematic form a register-trans- Vlator to whichthe invention can be applied. The translator has a code cycle containingall codes for which translations will be needed and which are presentedto a coincidence detector to which is also applied the codes Vcontainedin :the register. The `translater also has a translation cyclecontaining translations of all the codes and synchronisedwi-th the codecycle. The translations `are applied to a coincidence gate CG to whichthe output of the coincidence detector is also applied. Thus, when thecoincidence detector operates on coincidence between the codepresentedfrom the code cycle and that presented from the register a signal isapplied togate CG which Y opens the gate for a predetermined time.v'During that time the translation of the code in the register passesinto the translation storage.

YIn FIG. 7, which shows the register-translator in more detail, digitsare stored in the register REGI using a two out of iive code withreference to a source of l microsecond pulses operating in a 20D-pulsecycle. That is to say, tive pulses, allotted in combinations of twopulses, to represent the digits l 9, 0. 'Each of a number of commonpoints CP1, CP2 OPn represent code and translation positions whichtogether may occupy up to one cycle of the ZOOQI microsecond pulses.lEach code and translation point is thus characterised by a long pulsewhose duration is equal :to ZOO-l microsecond pulses but a long pulsemay characterise more thanone'code and translation point, because the'code and translation points areV operated cyclically and the number N oflong pulses in a cycle is determined by a number of factors includingthe time available for code comparison and receipt of translation.

The first code point and its corresponding translation point in thecycle are joined respectively to input tags C1 and T1 of common pointCP1. The second code point and its corresponding translation point arejoined respectively to tags C2 and T2 of common point CP2 and so on. lfn is equal to then the hundredth code and its translation are joinedrespectively to tags Cn and If the number of codes is greater than 100then the code and translation points lOl are joined respectively to tagsCCI and yTCI of common point CP1, code *and translation points 102 arejoined respectively to tags CCZ and TG2 of common point CP2 and so on.

Each tag C is attached to a code 'wire CPW which is threaded `through apredetermined selection of toroidal cores Ril-'R30 which form lowimpedance pulse sources. The rings are arranged in sets `of tive, eachset representing one digit of a six-digit number. ln' a set, thepossible values of the digit are represented by combinations of tworings. Thus, each code wire passes through two 5 rings in each set. Thecores may consist, for example, ofrings of about 1A inch square crosssection of thin (2 mils) mumetal spiraily wound or of ferrite material.Each ring has a primary winding PW to which is applied from pulse traingenerator PG one of the pulses -Pl-P30 required to make up the code andtranslation. The code wire OPW forms a single turn secondary winding oflow impedance in which a pulse output of value Ep volts can be produced.

The arrangement of feeding pulses to the toroidal cores may be as shownin FIG. 7 in which each pulse is generated by an individual source, orit may take other forms such as shown in FIGS. 2 and 3.

Similarly each tag T has a translation Wire TPW attached to it which ispassed through a combination of the rings taken two from each set ofrings as explained above in the case of the code wires.

After the code and translation wires have been threaded through therequired rings they are joined to output tags designated in like mannerto the input tags i.e. input tag C1 is connected to output tag C1 and soon.

Thus, in FIG. 7 it will be seen that a code is built up on a code wireby passing the wire through a selection of the rings each of which issupplied with one of a number of pulse trains designated P1-P30 of a 100pulse cycle. The input appearing on a code wire thus consists of aselection of l2 of the pulses P1-4P30. The translations are built up ina similar fashion. Further, it will be appreciated that as each commonpoint is fed with a long pulse of duration equal to that of a cycle of200 pulses then pulses P1 `to P30 appear twice during one long pulsei.e. they appear rstly at positions 1 to 30, and

secondly at positions 101 to 130 in the 20D-pulse cycle.

In addition to passing through the translation rings, the translationwires may also pass through rings marked special instructions in FIG. 7.The special instructions rings are supplied with pulses in positions notalready allocated for the codes or translations and in FIG. 7 positionsP40 to P50 are used. The special instructions rings are .for use inconnection Iwith the translation wires only and serve to provideinstruction to the translation input circuit, for example, an indicationof when the translation received by the input circuit should be sentout.

Thus, in FIG. 7, a code appears in pulse positions P1 P30 and thetranslation in pulse positions P101-P130 and P140-P150 in the 20G-pulsecycle. There are therefore a certain number of unused pulse positions inthe ZOO-pulse cycle.

The terminals C1, C2, etc. are commoned through gating rectiers MR to aresistor R1 or other suitable impedance which is Ibiased by a positivepotential E. Terminals T1, T2 etc. are similarly connected to a resistorR3. It is arranged that the pulse voltages Ecp and that applied to thewinding-s PW and now designated Ep both tend to make the rectiers MRconduct, but that although either Ecp or Ep alone is less than E anddoes not produce an output across resistor R1, etc. the sum of Ecp AandEp is greater than E so that the coincidence of the pulses produces anoutput across the resistors R1, etc. The codes which are wired on toterminals C1, C2, etc. thus appear in sequence across the resistor R1.The voltage across R1 is applied to a pulse reshaping device CPRI whichmay consist of an amplier and level discriminator and may include meansfor retirning the pulses.

Because the code and translation wires share the rings it is necessaryto gate out the pulses on the code Wire during the rst 100 pulsepositions of .the long pulse and to gate out the pulses on thetranslation wires during the second 100 pulse-positions of the longpulse. (This is achieved by coincidence gates CG1, CG2 and bycoincidence gates TG1, TG2 Thus, in the example shown in F-IG. 7 codecoincidence gates CGI, CGI

are each supplied with pulse trains P1 to 'P30 to gate the code pulsesand translation coincidence gates TG1, TG2 are each supplied with pulsetrains P101 to P in order to gate the pulses of pulse trains P1 to 'P30in positions 101 to 130 and the pulses of pulse trains yP40 to P50 inpositions 140 to 150 of the long pulses.

FIG. 7 also shows the coincidence detectors in more detail. Eachdetector consists' of two gates SG1, SGZ

and a trigger circuit TC. fThe trigger circuit when not inhibitedconnects a lD.C. condition on its output lead DCL applied to registercoincidence gate RGL Each trigger has a start lead ST whichbrings thetrigger to an uninhibited condition at the commencement of each 200-pulse cycle. The code cycle in the register operates in the same pulsepositions as the code cycle applied to the coincidence gates CGl, CGZ.1. in the translator and coincidence is sought between pulses appearingon a translator code output lead such as CO1 and the code in theregister. Whenever coincidence is not lfound the trigger is immediatelyreset thereby removing the D.C. condition on lead DCL. If coincidence isfound for each one of the digits forming the code the trigger remainsoperated so that the translation pulses are gated by P101 to P150 andare fed via RGI into the translation storage.

FIG. 8 shows the waveforms of pulse trains for the circuit of FIG. 7 butit will be understood that only cer tain of the pulse positions of the20G-pulse cycle are used in the embodiment described above withreference to FIG. 7.

The form of pulse generating system employing toroidal core transformersis particularly suitable for registertranslators since it is extremelyeconomical in equipment. Its memory is formed by threading the code andtranslation wires through the rings and each wire is terminated at eachend on individually numbered tags to facilitate removal when a code ortranslation has to be changed. It will be understood that the translatoris extremely exible and is not restricted to the number of digitsemployed in the example described above or to the particular arrangementof pulses.

I claim:

1. A register translator comprising in combination a plurality oftransformer cores, an input winding for each core, a plurality of pulsetrain generators, connections from said generators to said inputwindings, a number of code wires each inductively coupled by said coresto a selection of said input windings, and, a number of translationwires each inductively coupled by said cores to -another selection ofsaid input windings, each translation wire corresponding with one ofsaid code wires, rectiers series connected with said code wires and withsaid translation wires, biassing means for rendering said rectiersnormally nonconductive, pulsing means connected to both said code Wiresand said translation wires, coincidence detection means, means forcyclically presenting coded pulses to said detection means, means forconnecting said code wires to said detection means, translation storageapparatus, gating means connected between said translation wires andsaid translation storage apparatus for gating into said storageapparatus the output of a translation wire upon coincidence beingdetected by said detecting means.

2. A register translator comprising in combination a plurality oftoroidal transformer cores, -a rst `group of pulse train sources ofequal duration pulses, an input winding on each of said cores, electricleads connecting each winding to a different one of said pulse trainsources, a number of code wires each of which is threaded through aIselection of said cores, and, a number of translation wires, eachtranslation wire corresponding with one of said code wires and beingthreaded through another combination of said cores, rectii'lers inseries connection with said code and translation wires, biassing meansfor rendering lsaid rectiers normally non-conducting, a second sourceofpulse trains -the pulsesofwhch are yof a'duration atleast equal to thesum of the durations of the vpulses from said -rst group of pulse'trainsources, con

nectons from said second lsource yto each code and translation Wire,coincidence `detecting meansl connected to said code Wires,means forcyolically Vpresenting coded pulses `to said detection means, gatingmeans connected tosaid translation leads, `a translation store connectedto said'gating means and a connection from the .latter to said detectionmeans whereby said gating means is rendered operative on the detectionof coincidence by said detection means.

References Cited in the le of this patent UNITED STATES PATENTS DimondOct. 14, Rosenberg 'et al. vOct. 5, Saltz et al. Oct. 5, Couniha-n etal. Apr. 3, Lund a- July 3, Rajchman et al. Jan. 1, Chien Mer. 5,Stuart-Williams Oct. 8, Binden et al Aug. 26, Nettleton Sept. 23,

